This application claims the benefit of U.S. Provisional Application Serial No. 60/335,691 filed Oct. 2, 2001, which is hereby incorporated by reference.
The present invention relates to enzymatic methods and compositions for removing excess dye from dyed or printed materials, such as textiles, and to enzymatic methods and compositions for dyeing such materials.
A major problem involved with the use of disperse dyes for dyeing or printing of textile materials made from polyester fibers, polyester-containing blends and other fibers and fiber blends, is the tendency of these dyes to aggregate and deposit on the surface of the dyed or printed material. As a result of this residual dye formation, washfastness and wetfastness of the textile material is negatively affected, that is, the unintentional staining of other materials resulting from dyes that migrate from a dyed or printed fabric to another fabric during washing or wetting, often seen when white laundry becomes colored during washing. In addition to washfastness and wetfastness, residual dyes can also undermine the brightness of a shade as well as affect sublimation and crockfastness results of the dyed or printed material.
In order to improve the quality of textile materials, textile manufactures can select dyes that migrate as little as possible during washing. Alternatively, or in addition, textile manufactures can remove excess disperse dyes from newly prepared textiles in post-clearing or after-clearing processes. Traditional after-clearing processes involve repeated water rinses and/or chemical treatments, such as, reduction clearing processes, in which a dyed or printed fiber is treated with a strong alkaline reducing bath, usually containing sodium hydrosulfite and caustic soda. Reduction clearing processes, however, require high temperatures and alkaline conditions, which may damage the fabric and are expensive and time consuming to carry out.
Improvements in removing excess dye from dyed or printed materials, such as textile materials, are therefore desired.
One aspect of the present invention relates to methods and compositions for removing excess dyes, such as poorly soluble disperse dyes, that aggregate and deposit on the surfaces of dyed and/or printed materials. In accordance with the present invention, improvements to dyed and/or printed materials are obtained by treating a dyed and/or printed material, such as textile materials, paper materials, and films, with an esterase. Improvements resulting form the esterase treatment include, for example, improvements in washfastness, wetfastness, crockfastness, sublimation, and/or color quality (such as, for example, brightness) of dyed and/or printed materials.
Another aspect of the present invention relates to methods for printing or dyeing materials, such as textile materials, paper materials, and films. In accordance with this aspect of the present invention, a material is dyed or printed by dyeing and/or printing the material with a combination of a dye that is affected by esterase treatment and a dye that is not affected by esterase treatment, and after dyeing or printing the material, treating the material with an esterase. In an embodiment of this aspect of the present invention, a dye that is affected by esterase treatment, such as a disperse dye, can be used as a ground shade for a textile material, in combination with a dye, such as an illuminating dye, that is not affected by esterase treatment.
Yet another aspect of the present invention relates to methods for printing or dyeing materials, such as textile materials, paper materials, and films. In accordance with this aspect of the present invention, a combination of materials is dyed or printed by dyeing and/or printing the combination of materials (such as a fiber blend) with a dye that is affected by esterase treatment. In an embodiment of this aspect of the present invention, a dye that is affected by esterase treatment, such as a disperse dye, dyes one portion of the material in the combination, such as polyester, and subsequent to esterase treatment, which in this embodiment changes the affinity characteristics of the dye, the esterase modified residual dye dyes another portion of the material in the combination, such as wool, by virtue of the new affinity characteristics of the modified residual dye. In an embodiment of this aspect of the present invention, two materials with different dyeing properties, such as polyester and wool, are dyed with at least one dye whose affinity characteristics, such as hydrophobic versus ionic, are modified during the dyeing process by treatment with an esterase.
Yet another aspect of the present invention relates to dyed or printed materials, such as, for example, textile materials, paper materials and films prepared by the methods of the present invention.
Although not limited to any one theory of operation, the enzymatic treatment of dyed and/or printed materials according to the present invention is believed to improve the solubility of poorly soluble dyes and/or to decrease the affinity of dyes for materials, thereby improving the removal of excess dyes that aggregate and deposit on the surface of dyed and/or printed materials. In preferred embodiments, the methods of the present invention can eliminate the need for expensive and harsh chemical after-clearing processes, such as the use of heavy metal salts, and significantly reduce water usage.
In a preferred embodiment of the invention, excess dye can be removed from dyed or printed materials, such as textile materials, paper materials or films, by treating the printed or dyed material with at least one esterase. Textile materials include, for example, fabrics, yarn, fiber, and garments. The textile materials can be made from synthetic materials, and blends of natural and synthetic materials. Preferably, blends of natural and synthetic materials comprise at least 20%, more preferably at least 40%, even more preferably at least 60%, most preferably at least 80%, and in particular at least 95% of a synthetic material. Examples of synthetic materials, include, for example, modified cellulose (e.g. acetate, diacetate and triacetate), polyamide (e.g. nylon 6 and 6,6), polyester (e.g., poly(ethylene terephthalate)), acrylic/polyacrylic, and polyurethane (e.g., spandex). Examples of natural materials, include, for example, regenerated cellulosics (e.g., rayon), solvent spun cellulosics (e.g., lyocel and tencel), natural cellulosics (e.g., cotton, flax, linen, and ramie) and proteins (e.g., wool and silk). The term xe2x80x9csyntheticxe2x80x9d as used herein is intended to mean non-naturally occurring or man-made. Films include synthetic films, such as films made of polymers, such as, modified cellulose, polyamide, polyethylene and polypropylene. Paper materials include paper made from natural and synthetic materials.
In a preferred embodiment, the present invention is used to remove dyes and dye intermediates, which contain at least one ester chemical group and can be hydrolyzed by an esterase. Generally, after dyeing or printing a material, such as a textile material, excess dye is present as an aggregate or deposit on the surface of the dyed and/or printed material. The methods of the present invention can be used to remove this excess dye. Dye present inside the material, such as inside a textile material, is protected or generally protected from the enzyme treatment process. Although not limited to any one theory of operation, it is believed that esterase treatment of dyed and/or printed material results in removal of excess dye by improving the solubility of the dye and/or reducing the affinity of the dye for the material in accordance with or similar to the following non-limiting reaction scheme: 
In a preferred embodiment, the present invention is directed to the use of esterases to remove excess disperse dyes from dyed and/or printed materials. Disperse dyes are typically nonionic compounds that have very limited solubility in water, and usually contain at least one ester group, such as an acetyl group, xe2x80x94Oxe2x80x94COxe2x80x94CH3. Disperse dyes include, for example, azo dyes (such as, for example, mono-ester azo, diester azo and other ester azo dyes) and benzo difuranone dyes. Non-limiting examples of disperse dyes include, for example, Disperse Blue 79 (AAKASH Chemicals and Dyestuffs), Dispersol Red C-4G (BASF), Dispersol Brown C-3G (BASF), Dispersol Blue XF 55 (BASF), Disperse Red 167 (AAKASH Chemicals and Dyestuffs), Dispersol Brilliant Red D-SF (BASF), Dianix Scarlet SE-3G (DyStar).
As used in accordance with the present invention, an xe2x80x9cesterasexe2x80x9d refers to an enzyme which is able to hydrolyze an ester bond. More preferably, an esterase is a carboxylic ester hydrolase, such as, for example, cutinase, lipase, and carboxylesterase. Non-limiting examples of esterases suitable for use in the present invention include: arylesterase, triacylglycerol lipase, acetylesterase, acetylcholinesterase, cholinesterase, tropinesterase, pectinesterase, sterol esterase, chlorophyllase, L-arabinonolactonase, gluconolactonase, uronolactonase, tannase, retinyl-palmitate esterase, hydroxybutyrate-dimer hydrolase, acylglycerol lipase, 3-oxoadipate enol-lactonase, 1,4-lactonase, galactolipase, 4-pyridoxolactonase, acylcarnitine hydrolase, aminoacyl-tRNA hydrolase, D-arabinonolactonase, 6-phosphogluconolactonase, phospholipase A1,6-acetylglucose deacetylase, lipoprotein lipase, dihydrocoumarin lipase, limonin-D-ring-lactonase, steroid-lactonase, triacetate-lactonase, actinomycin lactonase, orsellinate-depside hydrolase, cephalosporin-C deacetylase, chlorogenate hydrolase, alpha-amino-acid esterase, 4-methyloxaloacetate esterase, carboxymethylenebutenolidase, deoxylimonate A-ring-lactonase, 2-acetyl-1-alkylglycerophosphocholine esterase, fusarinine-C ornithinesterase, sinapine esterase, wax-ester hydrolase, phorbol-diester hydrolase, phosphatidylinositol deacylase, sialate O-acetylesterase, acetoxybutynylbithiophene deacetylase, acetylsalicylate deacetylase, methylumbelliferyl-acetate deacetylase, 2-pyrone-4,6-dicarboxylate lactonase, N-acetylgalactosaminoglycan deacetylase, juvenile-hormone esterase, bis(2-ethylhexyl)phthalate esterase, protein-glutamate methylesterase, 11-cis-retinyl-palmitate hydrolase, all-trans-retinyl-palmitate hydrolase, L-rhamnono-1,4-lactonase, 5-(3,4-diacetoxybut-1-ynyl)-2,2xe2x80x2-bithiophene deacetylase, fatty-acyl-ethyl-ester synthase, xylono-1,4-lactonase, N-acetylglucosaminylphosphatidylinositol deacetylase, cetraxate benzylesterase, acetylalkylglycerol acetylhydrolase, and acetylxylan esterase.
The selection of an esterase for use in the treatment is generally based on the type of dye or dyes which were used to dye or print the material and the specificity of a particular esterase for a dye or dyes, such as, the type of ester bond the esterase hydrolyzes. The esterase treatment of the present invention can involve treatment with a single type of esterase, such as a cutinase, or treatment with one or more esterases, such as two or more esterases, three or more esterases, etc., for example, the combination of a cutinase and a lipase or the combination of various types of lipases. The selection of an esterase can also be based on the conditions of the treatment process, such as, for example, pH and temperature, by selecting an esterase that works best under the process conditions. In a preferred embodiment, the esterase is a lipase (triacylglycerol ester hydolyases), a cutinase, a suberinase, a carboxylicesterase or combinations thereof. A preferred lipase is Candida antarctica Lipase B (available from Novozymes A/S). A preferred cutinase is the fungal cutinase derived from Humicola insolens (available from Novozymes A/S). In a more preferred embodiment, the esterase is a carboxylesterase. Carboxylesterases have wide specificity, and can therefore be used in removing or discharging a wide variety of disperse dyes. A particularly preferred carboxylesterase is the porcine liver carboxylesterase (available from Sigma).
The esterase may be derived or obtained from any origin, including, bacterial, fungal, yeast or mammalian origin. The term xe2x80x9cderivedxe2x80x9d means in this context that the enzyme may have been isolated from an organism where it is present natively, i.e. the identity of the amino acid sequence of the enzyme are identical to a native enzyme. The term xe2x80x9cderivedxe2x80x9d also means that the enzymes may have been produced recombinantly in a host organism, the recombinant produced enzyme having either an identity identical to a native enzyme or having a modified amino acid sequence, e.g. having one or more amino acids which are deleted, inserted and/or substituted, i.e., a recombinantly produced enzyme which is a mutant and/or a fragment of a native amino acid sequence or an enzyme produced by nucleic acid shuffling processes known in the art. Within the meaning of a native enzyme are included natural variants. Furthermore, the term xe2x80x9cderivedxe2x80x9d includes enzymes produced synthetically by, e.g., peptide synthesis. The term xe2x80x9cderivedxe2x80x9d also encompasses enzymes which have been modified e.g. by glycosylation, phosphorylation, or by other chemical modification, whether in vivo or in vitro. The term xe2x80x9cobtainedxe2x80x9d in this context means that the enzyme has an amino acid sequence identical to a native enzyme. The term encompasses an enzyme that has been isolated from an organism where it is present natively, or one in which it has been expressed recombinantly in the same type of organism or another, or enzymes produced synthetically by, e.g., peptide synthesis. With respect to recombinantly produced enzymes the terms xe2x80x9cobtainedxe2x80x9d and xe2x80x9cderivedxe2x80x9d refers to the identity of the enzyme and not the identity of the host organism in which it is produced recombinantly.
The esterase may also be purified. The term xe2x80x9cpurifiedxe2x80x9d as used herein covers esterase enzymes free from other components from the organism from which it is derived. The term xe2x80x9cpurifiedxe2x80x9d also covers esterases free from components from the native organism from which it is obtained. The esterases may be purified, with only minor amounts of other proteins being present. The expression xe2x80x9cother proteinsxe2x80x9d relate in particular to other enzymes. The term xe2x80x9cpurifiedxe2x80x9d as used herein also refers to removal of other components, particularly other proteins and most particularly other enzymes present in the cell of origin of the esterase. The esterase may be xe2x80x9csubstantially pure,xe2x80x9d that is, free from other components from the organism in which it is produced, that is, for example, a host organism for recombinantly produced esterases. In preferred embodiment, the esterases are at least 75% (w/w) pure, more preferably at least 80%, at least 85%, at least 90%, at least 95%, at least 96%, at least 97%, at least 98%, or at least 99% pure. In another preferred embodiment, the esterase is 100% pure.
The term esterase also includes any auxiliary compounds or conditions to assist the enzyme""s catalytic activity, which may or may not be naturally present in the reaction system.
The esterase may be in any form suited for the use in the treatment process, such as e.g. in the form of a dry powder or granulate, a non-dusting granulate, a liquid, a stabilized liquid, or a protected enzyme. Granulates may be produced, e.g. as disclosed in U.S. Pat. Nos. 4,106,991 and 4,661,452, and may optionally be coated by methods known in the art. Liquid enzyme preparations may, for instance, be stabilized by adding stabilizers such as a sugar, a sugar alcohol or another polyol, lactic acid or another organic acid according to established methods. Protected enzymes may be prepared according to the method disclosed in EP 238,216.
The removal of excess disperse dye from dyed and/or printed materials, according to the present invention, can be carried out by any suitable method available in the art. Preferably, removal comprises contacting, rinsing or washing of a dyed and/or printed material with an aqueous rinse liquor or wash comprising at least one esterase. The removal of excess dye may be carried out at any time after the dyeing and/or printing process, including, for example, immediately following the dyeing or printing of the material, such as on a newly dyed and/or newly printed textile material, or following additional processing steps. The removal of excess dye according to the present invention is preferably performed in a batch mode or continuous mode.
The removal of excess disperse dyes from dyed and/or printed textile material, according to the present invention, can be carried out using any suitable equipment available in the art for after-clearing processes. The processes of the present invention may preferably be applied in a winch, a beck, a jet dyer, an open-width washing machine, a J or U box, a steamer, or any other equipment suitable for rinsing or washing materials.
The treatment with an esterase may be carried out at conditions chosen to suit the selected enzymes according to principles well known in the art. It will be understood that each of the reaction conditions, such as, e.g., concentration/dose of enzyme, pH, temperature, and time of treatment, may be varied, depending upon, e.g., the source of the enzyme, the type of dye, the method in which the treatment is performed, the extent of excess dye removal desired. It will further be understood that optimization of the reaction conditions may be achieved using routine experimentation by establishing a matrix of conditions and testing different points in the matrix.
Preferably, the temperatures, pH, treatment time and concentration are based on the optimal conditions for the enzyme or enzymes used. Preferably, the reaction mixture of the material, for example, a textile, and enzyme is incubated or reacted at a temperature of between about 25-100xc2x0 C., more preferably between about 50-70xc2x0 C. Preferably, the reaction time is between about 1-120 minutes, more preferably about 10-40 minutes. The enzymatic treatment may be conducted at any suitable pH, such as for example, in the range of about 4 to about 11, such as, at a pH of about 6 to about 8.
The esterases are added in an effective amount. The term xe2x80x9ceffective amountxe2x80x9d means an amount sufficient to achieve the desired effect. Preferably, the esterases are added in an amount from about 0.1 mg enzyme protein to about 1000 mg/L liquor, more preferably in an amount from about 1 to 500 mg/L, such as, 1 mg to about 200 mg/L, such as, 80 to about 100 mg/L.
The present invention also relates to methods for printing or dyeing materials, such as textile materials, paper materials and films, using the combination of at least one dye that is affected by esterase treatment and at least one dye that is not affected by esterase treatment, and after dyeing or printing the material, treating the material with an esterase. The phase xe2x80x9caffected by esterase treatmentxe2x80x9d means that the solubility of the dye is increased by treatment with an esterase and/or the affinity of the dye for the material is decreased by treatment with an esterase and/or the dye can be discharged or loosed from a material, such as a polyester textile material, by treatment with an esterase. In a preferred embodiment of this aspect of the present invention, a textile material is dyed and/or printed with a dye that is affected by esterase treatment and a dye that is not affected by esterase treatment, and following dyeing, the dyed and/or printed material is treated with an esterase to discharge the excess disperse dye. In another preferred embodiment, the dye that is affected by esterase treatment, as described herein, can be used as a ground shade for a dyed and/or printed textile material, such as, by dyeing the textile material with a combination of a disperse dye and a dye that is not affected by esterase treatment, such as an illuminating dye, and following dyeing, subjecting the dyed and/or printed material to an esterase treatment, as described herein. Examples of dyes which are generally not affected by esterase treatment include, for example, an AQ or mono-azo type dye which do not contain at least one ester bond
The present invention further includes textile materials, such as, for example, fabrics, yarn, fiber, garments, paper materials and films, prepared by the methods described herein. The materials may also be subject to additional processes. For example, for textile materials, the preparation may include the application of finishing techniques, and other treatment processes, such as imparting antimicrobial properties (e.g., using quaternary ammonium salts), flame retardancy (e.g., by phosphorylation with phosphoric acid or urea), increasing absorbency (by coating or laminating with polyacrylic acid), providing an antistatic finish (e.g., using amphoteric surfactants (N-oleyl-N,N-dimethylglycine)), providing a soil release finish (e.g., using NaOH), providing an antisoiling finish (e.g., using a fluorochemical agent), and providing an antipilling finish (e.g., using NaOH, alcohol).
The invention will further be described by reference to the following detailed examples. These examples are provided for the purpose of illustration only, and are not intended to be limiting unless otherwise specified.